Logic pro acting weird and crashing

Ok guys so I am running logic pro 9.1.3 on my mid 2010 mac mini with dual core 2.4ghz processor with 4gb of ram. last night i was opening some old sessions that i had not ran in awhile just to listen to them and it would crash on some of them after maybe 30 seconds of playback. i come back this morning and open up logic and first i notice that it opens but the load screen doesnt come up at all it just bounces on the dock then stops but its open. i can open any session but as soon as i hit play it crashes. and i also cant create any audio or instrument tracks, its not even in the list of tracks. I have trashed the preferences and ive reinstalled twice, has anyone had trouble with this or have any idea what could be going wrong. i do not get a crash report or a anything saying it unexpectedly quit, it just disappears.

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